The hottest second-generation RFID tag standard su

The second generation RFID tag standard surfaced (III)

most importantly, as pointed out in several articles written by Dr. Daniel Engels, director of the automatic identification center, in addition to acting as a broadband backscatter "transmitter", the tag is also a "broadband receiver" - the tag knows nothing about the channel used by the reader

the receiver on the label is like a transistor radio, because the ability to select the spectrum is completely subject to the characteristics of the label antenna. In fact, this is implemented by the second generation specification, which requires labels to work between 860MHz and 960MHz. Therefore, a specific tag will receive all signals transmitted by all readers within the effective distance at the same time, even if the reader works in the dense reader mode, so different channels are used. This is the fundamental problem of the current generation of RFID. The most effective solution is to adopt an accurate and time-based reader synchronization mechanism. This mechanism is designed to prevent two readers from trying to communicate with the same tag at the same time. Because of this, the time-based reader synchronization mechanism is the most important method to manage the dense reader environment. Unfortunately, the second generation dense reader mode does not overcome this major shortcoming of the broadband receiver on the second generation tag

dense reader mode should be considered as the first step towards working in a dense reader environment. But it is not a panacea to overcome the limitations of today's passive RFID technology. The fundamental problems of dense reader environment (including broadband transmission and reception of tags) still need to be solved by future generations of passive RFID technology

surpass the second generation EPC

EPC CLA8, 1-point-to-point SS structure

EPC tag class structure is often misunderstood. The upward and downward movement of the C10 chuck, that is, the tension and compression, is controlled by the main oil source under the console. The clamping of the upper and lower test pieces is completed by the clamping driving oil source. Lass is not the same as "generation". Class describes the basic functions of a tag -- for example, whether there is memory or battery in it. Refers to the major version number of the label specification. Generally speaking, the full name of the second generation EPC is actually the second generation EPC class 1, which indicates that the specification refers to the second major version of the specification, which is for tags that have a write once memory

class V tags are actually readers. They can be other class I, class II and class III tags, and can also communicate with other class IV tags and each other wirelessly

class iv

class IV tags are active tags. They can carry out broadband and peer-to-peer communication with other active tags and readers in the same frequency band

class iii

class III tag is a semi passive RFID tag. They can communicate in broadband

class ii

class II tags are passive tags with additional functions such as memory or encryption

class i/class 0

class 0/class I tags are read-only passive identification tags

class 0 was added to the first generation system as part of the process described above after the class 1 specification was drafted. The class 1 tag (the second generation tag is an example) contains a write once memory, which is used to save the electronic product code. The class 2 tag adds memory that can be changed periodically to store additional data - such as data from built-in sensors. Class 3 standard adds batteries to extend the distance of reading labels and improve reliability, but it basically belongs to passive backscatter labels. Class 4 tags are actually active tags that can communicate with other class 4 Tags and readers. The class 5 tag is not a tag at all. It is actually a wireless reader

epc class structure the purpose of this rule is to provide a modular structure, covering a series of possible types of label functions. For example, the communication protocol of battery powered tags should be the same as that of tags without batteries, but the necessary commands to support batteries are added. This keeps the protocol simple. If the battery on the battery powered label fails or fails, the label is completely similar to the label without battery, and it still has some practical functions for end users. This modular idea is much simpler in theory than in practice - however, technology tends to continue to integrate, and the EPC industry is also eager to provide a modular, multi-functional label protocol stack. This adds another variable to the many tags that the reader infrastructure must be able to apply. Since the second generation class 1 eliminates the difference between Class 0 and class 1, the next step that may appear is to add a battery tag to the system. This may solve the problem of punching force difference in thermoforming of recycled materials, which is embodied in the second generation class 3 label - which may point out the way for a new generation of products